package com.huaxinkai.mobile.util.common;

import java.security.MessageDigest;
/**
 * Sha1 工具类
 * @author liuzh
 * @date 2017年1月6日上午12:47:18
 */
public class Sha1Util {
	/**
	 * 获取Sha1
	 * @param str
	 * @return
	 */
	public static String getSha1(String str){
        if(str==null||str.length()==0){
            return null;
        }
        char hexDigits[] = {'0','1','2','3','4','5','6','7','8','9',
                'a','b','c','d','e','f'};
        try {
            MessageDigest mdTemp = MessageDigest.getInstance("SHA1");
            mdTemp.update(str.getBytes("UTF-8"));

            byte[] md = mdTemp.digest();
            int j = md.length;
            char buf[] = new char[j*2];
            int k = 0;
            for (int i = 0; i < j; i++) {
                byte byte0 = md[i];
                buf[k++] = hexDigits[byte0 >>> 4 & 0xf];
                buf[k++] = hexDigits[byte0 & 0xf];      
            }
            return new String(buf);
        } catch (Exception e) {
            return null;
        }
    }
}
